Long-term persistence of TNF-inhibitor treatment in patients with psoriatic arthritis. Data from the British Society for Rheumatology Biologics Register.

Background: Long-term effectiveness of tumour necrosis factor alpha inhibitors (TNFi) has mainly been explored in patients with rheumatoid arthritis (RA) and the data available on patients with psoriatic arthritis (PsA) includes limited follow-up.

Objective: Investigate long-term effectiveness of first TNFi in a PsA population by describing treatment persistence, identify factors associated with 5-year persistence and further investigate comparative long-term effectiveness of subsequent TNFi treatments through persistence to treatment.

Methods: Patients with a rheumatologist diagnosis of PsA receiving their first TNFi registered in the British Society for Rheumatology Biologics Register (BSRBR) (2002-2006) were included.